Method and system for adaptive continuously variable transmission gear ratio control

• US 8,585,551 B2
• Filed: 01/27/2010
• Issued: 11/19/2013
• Est. Priority Date: 01/27/2010
• Status: Expired due to Fees

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Motor Engineering & Manufacturing North America Incorporated (Toyota Motor Corporation)
• Inventors: Choby, Jordan
• Primary Examiner(s): PANG, ROGER L
• Application Number:
  US12/695,093
• Publication Number:
  US 20110183810A1
• Time in Patent Office: 1,392 Days
• Field of Search: 477/37, 477/115, 477/120, 477/121, 477/132, 477/133, 477/143, 477/904, 477/905
• US Class Current: 477/120
• CPC Class Codes: F16H 59/48 Inputs being a function of acceleration
• CPC Class Codes: F16H 61/66 specially adapted for continuously variable gearings control of exclusively fluid gearing F16H61/38

Abstract

An automobile comprising a continuously variable transmission (“CVT”) system including an acceleration input device, a CVT, and a processor. The acceleration input device generates acceleration input data indicating an amount of change in the acceleration input device, and a rate of change in the acceleration input device. The CVT includes a power source and a transmission output system. The power source operates at a transmission input speed, while the transmission output system operates at a transmission output speed. The transmission input speed over the transmission output speed comprises a gear ratio. The processor analyzes the acceleration input data to determine a target gear ratio. The processor can instruct the CVT to change the gear ratio to the target gear ratio at a rate corresponding to the rate of change in the acceleration input device.

Claims

1. A continuously variable transmission system comprising:

a continuously variable transmission configured to operate at a gear ratio;

an acceleration input device configured to detect acceleration input data corresponding to a percent application of the acceleration input device; and

a processor connected to the continuously variable transmission and the acceleration input device, the processor configured to determine a rate of change in the percent application of the acceleration input device and continuously change the gear ratio at a rate of change that is substantially equal to the rate of change in the percent application of the acceleration input device throughout an entire spectrum of the rate of change in the percent application of the acceleration input device.

2. The system of claim 1 wherein the processor is configured to determine a target gear ratio such that a rate of change in the target gear ratio is substantially equal to the rate of change in the percent application of the acceleration input device, and the processor is further configured to change the gear ratio to match the target gear ratio.

3. The system of claim 1 wherein the continuously variable transmission includes

a power source configured to operate at a transmission input speed;

and

a transmission output device configured to operate at a transmission output speed, wherein the transmission input speed over the transmission output speed comprise the gear ratio.

4. The system of claim 1 wherein the continuously variable transmission includes or is coupled to a power source configured to operate at a transmission input speed, and the processor is configured to adjust the rate of change in the gear ratio by changing a rate of change in the transmission input speed to be substantially equal to the rate of change in the percent application of the acceleration input device.

5. The system of claim 4 wherein the processor is configured to increase the transmission input speed at a first rate of increase in the transmission input speed substantially equal to a first rate of increase in the percent application of the acceleration input device, and the processor is further configured to increase the transmission input speed at a second rate of increase in the transmission input speed substantially equal to a second rate of increase in the percent application of the acceleration input device that is is less than the first rate of increase in the percent application of the acceleration input device.

6. An automobile comprising:

a power source configured to operate at a transmission input speed;

a transmission output device configured to operate at a transmission output speed, wherein the transmission input speed over the transmission output speed comprise the gear ratio;

an acceleration input device configured to detect acceleration input data corresponding to a percent application of the acceleration input device; and

a processor connected to the power source, the transmission output device, and the acceleration input device, the processor configured to determine a rate of change in the percent application of the acceleration input device, determine a target gear ratio such that a rate of change in the target gear ratio is substantially equal to the rate of change in the percent application of the acceleration input data throughout an entire spectrum of the rate of change in the percent application of the acceleration input device, and continuously change the gear ratio throughout the entire spectrum of the rate of change in the acceleration input data to match the target gear ratio.

7. The automobile of claim 6 wherein the processor changes the gear ratio by changing the transmission input speed at a rate of change in the transmission input speed that is substantially equal to the rate of change in the acceleration input data.

8. The automobile of claim 7 wherein the processor is configured to increase the transmission input speed at a first rate of increase in the transmission input speed substantially equal to a first rate of increase in percent application of the acceleration input device, and the processor is configured to increase the transmission input speed at a second rate of increase in the transmission input speed substantially equal to a second rate of increase in the percent application of the acceleration input device that is less than the first rate of increase in the acceleration input.

9. A continuously variable transmission system comprising:

a continuously variable transmission configured to operate at a gear ratio;

an acceleration input device configured to detect acceleration input data corresponding to a percent application of the acceleration input device; and

a processor connected to the continuously variable transmission and the acceleration input device, the processor configured to determine a rate of change in the percent application of the acceleration input device and continuously change the gear ratio at a rate of change that is substantially equal to the rate of change in the percent application of the acceleration input device throughout a majority of an entire spectrum of the rate of change in the percent application of the acceleration input device.

10. The system of claim 9 wherein the processor is configured to determine a target gear ratio such that a rate of change in the target gear ratio is substantially equal to the rate of change in the percent application of the acceleration input device, and the processor is further configured to change the gear ratio to match the target gear ratio.

11. The system of claim 9 wherein the continuously variable transmission includes

a power source configured to operate at a transmission input speed;

and

a transmission output device configured to operate at a transmission output speed, wherein the transmission input speed over the transmission output speed comprise the gear ratio.

12. The system of claim 9 wherein the continuously variable transmission includes or is coupled to a power source configured to operate at a transmission input speed, and the processor is configured to adjust the rate of change in the gear ratio by changing a rate of change in the transmission input speed to be substantially equal to the rate of change in the percent application of the acceleration input device.

13. The system of claim 11 wherein the processor is configured to increase the transmission input speed at a first rate of increase in the transmission input speed substantially equal to a first rate of increase in the percent application of the acceleration input device, and the processor is further configured to increase the transmission input speed at a second rate of increase in the transmission input speed substantially equal to a second rate of increase in the percent application of the acceleration input device that is less than the first rate of increase in the percent application of the acceleration input device.

14. A continuously variable transmission system comprising:

a continuously variable transmission configured to operate at a gear ratio;

an acceleration input device configured to detect acceleration input data corresponding to a percent application of the acceleration input device that increases during a first time period and remains substantially constant during a second time period; and

a processor connected to the continuously variable transmission and the acceleration input device, the processor configured to determine a rate of change in the percent application of the acceleration input device and continuously change the gear ratio at a rate of change that is substantially equal to the rate of change in the percent application of the acceleration input device throughout the first time period and the second time period.

15. The system of claim 14 wherein the processor is configured to determine a target gear ratio such that a rate of change in the target gear ratio is substantially equal to the rate of change in the percent application of the acceleration input device throughout the first time period and the second time period, and the processor is further configured to change the gear ratio to match the target gear ratio.

16. The system of claim 14 wherein the continuously variable transmission includes

a power source configured to operate at a transmission input speed;

and

a transmission output device configured to operate at a transmission output speed, wherein the transmission input speed over the transmission output speed comprise the gear ratio.

17. The system of claim 14 wherein the continuously variable transmission includes or is coupled to a power source configured to operate at a transmission input speed, and the processor is configured to adjust the rate of change in the gear ratio by changing a rate of change in the transmission input speed to be substantially equal to the rate of change in the percent application of the acceleration input device.

18. The system of claim 16 wherein the processor is configured to increase the transmission input speed at a first rate of increase in the transmission input speed substantially equal to a first rate of increase in the percent application of the acceleration input device, and the processor is further configured to increase the transmission input speed at a second rate of increase in the transmission input speed substantially equal to a second rate of increase in the percent application of the acceleration input device that is less than the first rate of increase in the percent application of the acceleration input device.